Roadway repair is often accomplished by overlaying the existing pavement (whether of concrete or asphalt composition) with a new layer (often called a leveling course) of concrete, asphalt or other surfacing materials. Without prior surface treatment, however, this method of repair generally results in the application of insufficient quantities of paving material in the rutted, potholed or otherwise damaged areas, because the overlay will be applied at the same rate per unit of roadway width in damaged areas (which have a greater depth across the width) as in the undamaged areas. The resulting reduced density in the overlay of the previously damaged areas will lead to renewed rutting or other wear damage in the new pavement in relatively short order. However, by milling the surface of the damaged pavement, the milled surface may be rendered substantially flat so that newly added pavement will have a uniform thickness across the entire width of the roadway. In addition, a repaving technique that includes milling a thickness of old pavement and replacing it with an equivalent thickness of new pavement will return the elevation of the roadway to its initial level, whereas the placement of a leveling course atop damaged pavement will tend to raise the surface of the roadway or some portion thereof above its original elevation. This can require the raising of road shoulders, guardrails and manhole covers and the adjustment of overpass clearances, all of which are unnecessary if a proper milling technique is employed. A use of milling prior to repaving can also permit ready establishment of the proper road grade and slope, and thereby avoid drainage and safety problems. Furthermore, milling typically provides a rough surface that readily accepts and bonds with the new asphalt or other pavement overlay. Finally, milling can provide raw material that can be reclaimed for use in the production of new paving materials.
A milling machine is typically a wheeled or track-driven vehicle that is provided with a rotating drum that includes a plurality of cutting teeth. The drum is mounted in a housing on the frame of the machine and adapted to be lowered into contact with the road surface and rotated about a horizontal axis so as to cut into the surface to a desired depth as the machine is advanced along the roadway. Generally, the milling machine also includes a conveyor system that is designed to carry the majority of the milled material that has been cut from the roadway by the rotating drum to a location in front of, to the rear of or beside the machine for deposit into a truck for removal from the milling site. Sweeping machines are frequently required, however, to follow a milling machine in order to remove any milled material left behind by the milling machine prior to resurfacing.
Conventional sweeping machines typically employ a broom assembly comprising one or more brooms mounted for rotation about horizontal or vertical axes. Some conventional machines may operate by pushing the swept material to one side of the machine where it may be collected by a separate collecting device. Other conventional machines include a broom assembly and an integral assembly for collecting material swept by the broom or brooms. Such integral collecting assemblies may comprise vacuum systems for capturing the material swept by the brooms or discharge conveyors for transporting such material to a hopper or an adjacent truck. Most conventional sweeping machines having an integral collecting assembly are not enclosed or are not sufficiently enclosed to avoid leaving material on the roadway. Many such machines must make multiple passes along a roadway to clear the roadway sufficiently to allow for resurfacing.
Some conventional sweeping machines include broom assemblies which employ permanent brooms, while others employ replaceable brooms. Typically, a replaceable broom comprises a cylindrical broom tube of steel or other durable material having a plurality of bristles disposed around its outer periphery. Generally, a replaceable broom is attached to a conventional broom assembly by one or more locking mechanisms that must be unbolted, unpinned or otherwise removed in order to change the replaceable broom. Conventional sweeping machines that employ replaceable brooms typically hold the broom tube inside the machine with a pair of drive hubs, one on each end. These hubs are generally mounted in bearings that are bolted or otherwise attached to arms on the sweeping assembly that may be raised or lowered to move the broom into and out of contact with the roadway.
In some machines that employ replaceable brooms and partially enclose the sweeping assembly only on the sides (i.e. with end gates), the broom may be removed for replacement from the back of the assembly. However, these machines do not sufficiently contain the swept material so that it may be removed by an integral collecting assembly. In some machines that employ replaceable brooms and partially enclose the sweeping assembly at the rear and sides, the broom tube may be removed only by disconnecting and removing multiple components from the sides of the sweeping assembly. This is time-consuming and may require skilled labor and tools to replace a broom. It would be desirable if a broom assembly for a sweeping machine with an integral collecting assembly could be provided that allowed for easier and quicker replacement of worn brooms.
Notes on Construction
The use of the terms “a”, “an”, “the” and similar terms in the context of describing the invention are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising”, “having”, “including” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The terms “substantially”, “generally” and other words of degree are relative modifiers intended to indicate permissible variation from the characteristic so modified. The use of such terms in describing a physical or functional characteristic of the invention is not intended to limit such characteristic to the absolute value which the term modifies, but rather to provide an approximation of the value of such physical or functional characteristic. All methods described herein can be performed in any suitable order unless otherwise specified herein or clearly indicated by context.
Terms concerning attachments, coupling and the like, such as “connected” and “interconnected”, refer to a relationship wherein structures are secured or attached to one another either directly or indirectly through intervening structures, as well as both moveable and rigid attachments or relationships, unless specified herein or clearly indicated by context. The term “operatively connected” is such an attachment, coupling or connection that allows the pertinent structures to operate as intended by virtue of that relationship.
The use of any and all examples or exemplary language (e.g., “such as” and “preferably”) herein is intended merely to better illuminate the invention and the preferred embodiments thereof, and not to place a limitation on the scope of the invention. Nothing in the specification should be construed as indicating any element as essential to the practice of the invention unless so stated with specificity. Several terms are specifically defined herein. These terms are to be given their broadest possible construction consistent with such definitions, as follows:
The terms “lower”, “bottom” and similar terms, when used in reference to a relative position or direction on or with respect to a vehicular sweeping machine, or an assembly, component or portion thereof, refer to a relative position or direction that is nearer the roadway on which the vehicular sweeping machine is placed for operation.
The terms “upper”, “top” and similar terms, when used in reference to a relative position or direction on or with respect to a vehicular sweeping machine or an assembly, component or portion thereof, refer to a relative position or direction that is farther away from the roadway on which the vehicular sweeping machine is placed for operation.
The term “forward sweeping direction” is the direction that the operator of the vehicular sweeping machine faces when he is seated in the normal position for the operator of the vehicular sweeping machine.
The term “sweeping diameter”, when used to describe a dimension of a broom, refers to the distance from the outer extent of a bristle of the broom to the outer extent of a bristle on the opposite side of the broom tube.
The term “in front of” and similar terms refer to an assembly, component or portion of a vehicular sweeping machine that is in the forward sweeping direction with respect to a reference point, assembly, component or portion of the vehicular sweeping machine.
The term “behind” and similar terms refer to an assembly, component or portion of a vehicular sweeping machine that is in the direction opposite the forward sweeping direction with respect to a reference point, assembly, component or portion of the vehicular sweeping machine.
The term “left”, as used herein to describe a direction or relative position of a vehicular sweeping machine or an assembly, component or portion of such a sweeping machine, refers to a position or orientation towards the left, from the perspective of the operator who is driving the machine in the forward sweeping direction.
The term “right”, as used herein to describe a direction or relative position of a vehicular sweeping machine or an assembly, component or portion of such a sweeping machine, refers to a position or orientation towards the right, from the perspective of the operator who is driving the machine in the forward sweeping direction.
The term “inside”, as used herein to describe a direction or relative position of an assembly, component or portion of a vehicular sweeping machine, refers to a position or orientation away from the outer periphery of the vehicular sweeping machine or component or portion thereof.
The term “outside”, as used herein to describe a direction or relative position of an assembly, component or portion of a vehicular sweeping machine, refers to a position or orientation towards the outer periphery of the vehicular sweeping machine or component or portion thereof.
The term “linear actuator” refers to an electric, pneumatic, hydraulic, electro-hydraulic or mechanical device that generates force which is directed in a straight line. Common examples of “linear actuators” are hydraulic and pneumatic actuators which include a cylinder, a piston within the cylinder, and a rod attached to the piston. By increasing the pressure within the cylinder on one side of the piston (over that on the opposite side of the piston), the rod will extend from the cylinder or retract into the cylinder.
The term “rotary actuator” refers to an electric, hydraulic or electro-hydraulic motor or other device that generates force that is directed along an arc or about a center of rotation.
The term “actuator” (without a qualifying adjective) refers to a linear actuator or a rotary actuator.